JP2008002969A - Rotary encoder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotary encoder capable of shortening a time for a bonding process of a rotary encoder rotator, and facilitating management of an adhesive. <P>SOLUTION: The rotary encoder 1 comprises the rotary encoder rotator 2 comprising a hub member 6 fixed to a rotating shaft which is a measuring object, a disk member 5 fixed to the hub member 6 and having a prescribed pattern, and a magnet 7 bonded to the hub member 6; a circuit board 4 for calculating a rotation amount of the measuring object based on a signal from the detected prescribed pattern; and a mold member 3 for rotatably storing the rotary encoder rotator 2. In the rotary encoder 1, the hub member 6 has a through-hole, and a photo-curing type adhesive filled in the through hole is cured, to thereby bond the hub member 6 to the magnet 7. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a rotary encoder.

Conventionally, in a rotary encoder, a rotary encoder rotating body is configured by adhering a disk member having a slit-shaped pattern to a rotating shaft connected to a motor with an adhesive (for example, see Patent Document 1).
Japanese Patent Laid-Open No. 10-2760

  However, the rotary encoder rotating body in the conventional rotary encoder can use an ultraviolet curable adhesive when one of the members to be bonded is optically transparent, but both of the members to be bonded are optically bonded. If it is opaque, an ultraviolet curable adhesive cannot be used, and a two-component mixed adhesive or a thermosetting adhesive must be used. Two-component mixed adhesives require strict time management of the adhesive because the properties of the adhesive change over time after two-component mixing, and thermosetting adhesives must be processed at high temperatures. There is a problem that the manufacturing process becomes complicated, such as the time for holding the adhesive member and raising and lowering the temperature.

  The present invention has been made in view of the above-described problems, and provides a rotary encoder that makes it possible to shorten the time for the bonding process of the rotary encoder rotating body and to manage the adhesive.

  In order to solve the above problems, the present invention provides a hub member fixed to a rotating shaft to be measured, a disk member fixed to the hub member and having a predetermined pattern, and a magnet bonded to the hub member. A rotary encoder comprising: a circuit board that calculates a rotation amount of the measurement object based on the detected signal from the predetermined pattern; and a mold member that rotatably accommodates the rotary encoder. The hub member has a through-hole, and the photocurable adhesive filled in the through-hole is cured to bond the hub member and the magnet.

  ADVANTAGE OF THE INVENTION According to this invention, the rotary encoder which makes time reduction of the adhesion process of a rotary encoder rotary body and management of an adhesive agent easy can be provided.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic configuration diagram of a rotary encoder having a rotary encoder rotating body according to an embodiment of the present invention.

  In FIG. 1, the rotary encoder 1 has a rotary encoder rotating body 2 held in a space surrounded by a main body mold member 3 and a main substrate 4. In the rotary encoder rotating body 2, a glass disk 5 in which a slit-like opening pattern is formed is bonded to a hub 6, and the hub 6 is bonded to a magnet 7. A cylindrical member 8 is provided at the center of the hub 6. The cylindrical member 8 is engaged with a rotating shaft of a motor (not shown), and the rotary encoder rotating body 2 is fixed to the rotating shaft of the motor with a disk set screw 9.

  The rotary encoder rotating body 2 is covered with the main body mold member 3 and is blocked from the outside. Further, a shield member 10 that covers the rotary encoder rotator 2 is provided above the rotary encoder rotator 2 of the main body mold member 3 to prevent entry of dust or the like into the area of the rotary encoder rotator 2 inside the main body mold member 3. is doing.

  Above the main body mold member 3, a main substrate 4 on which electric parts for performing various signal processing of the rotary encoder are mounted is fixed so as to cover the opening above the main body mold member 3.

  A light emitting element (not shown) is disposed below the glass disk 3 of the main body mold member 3, and a light receiving element (not illustrated) is disposed on the main body mold member 3 side of the main substrate 4 above the light emitting element. Has been. The shield member 10 positioned on the optical axis of the light emitting element and the light receiving element is provided with an opening (not shown) for allowing light from the light emitting element to pass through.

  The light from the light emitting element is turned on / off by the slit-shaped opening pattern formed on the glass disk 5, and the light from the light emitting element is detected by the light receiving element, thereby detecting the rotation of the motor. In this way, the rotary encoder 1 is configured.

  In the present embodiment, the rotary encoder rotating body 2 has an optically opaque hub 6 and magnet 7 bonded thereto. Hereinafter, this bonding step will be described with reference to FIG.

  FIGS. 2A and 2B are explanatory diagrams for explaining a bonding process of the rotary encoder rotating body according to the embodiment of the present invention. FIG. 2A is a process for positioning a magnet and a hub, and FIG. (C) shows the step of photocuring the adhesive.

  In FIG. 2A, a through hole 6 a is formed in the hub 6. Here, a case where four through holes 6a are provided will be described. However, the number of through holes 6a is not limited to this, and can be changed within a range in which a predetermined adhesive strength is maintained. The through hole 6a is preferably provided at a position symmetrical to the center of the disk-shaped hub 6 in consideration of the balance of adhesion.

  As shown in FIG. 2A, after positioning the magnet 7 at the center of the hub 6, the hub 6 and the magnet 7 are turned over as shown in FIG. At this time, the magnet 7 is supported on the hub 6 by magnetic force. Thereafter, the UV curable adhesive 22 is filled into the through hole 6 a of the hub 6 from the nozzle 21 of the adhesive applicator 20. After all the through holes 6a are filled with the ultraviolet curable adhesive 22, the ultraviolet curable adhesive 22 is irradiated with the ultraviolet light by the ultraviolet irradiation device 23 and solidified (see FIG. 2C). Thereafter, the glass disk 5 is bonded to the outer periphery of the hub 6. In this way, the rotary encoder rotating body 2 is configured. Irradiation with ultraviolet light may be performed for each through hole 6a or may be performed collectively.

  In the rotary encoder rotating body 2 having such a configuration, the ultraviolet curable adhesive 22 has a structure in which the magnet 7 generates an adhesive strength at the area of the through hole 6 a and the hub 6 at the thickness of the hub 6. The adhesive strength between the magnet 7 and the hub 6 is a combination of the magnetic force of the magnet 7 and the bonded portion of the ultraviolet curable adhesive 22.

  As described above, according to the embodiment of the present invention, the through hole 6 a is provided in the region where the magnet 7 of the hub 6 is bonded, and the ultraviolet curable adhesive 22 can be used for bonding the hub 6 and the magnet 7. By comprising, the time of an adhesion | attachment process can be shortened. Moreover, since the ultraviolet curable adhesive 22 is used, in-process management of the adhesive becomes easier as compared with the conventional two-component mixed adhesive and the thermosetting adhesive.

  Note that the adhesive is not limited to the ultraviolet curable adhesive, and other photocurable adhesives can be used. Further, when the ultraviolet curable adhesive 22 is filled in the through hole 6a, the ultraviolet curable adhesive 22 after solidification is supplied by supplying the ultraviolet curable adhesive 22 so as to be slightly larger than the diameter of the through hole 6a. However, it can be configured to have the function of a hook for hooking the hub 6, and the effect of increasing the adhesive force between the hub 6 and the magnet 7 can be achieved.

  The above-described embodiment is merely an example, and is not limited to the above-described configuration and shape, and can be appropriately modified and changed within the scope of the present invention.

It is a schematic block diagram of the rotary encoder which has the rotary encoder rotary body concerning embodiment of this invention. It is adhesion process explanatory drawing of the rotary encoder rotary body concerning embodiment of this invention, (a) is a positioning process of a magnet and a hub, (b) is a process of filling a through hole with an adhesive, (c) ) Shows the process of photocuring the adhesive.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rotary encoder 2 Rotary encoder rotary body 3 Main body mold member 4 Main board 5 Glass disc 6 Hub 7 Magnet 8 Cylindrical member 9 Disc part set screw 10 Shield plate 20 Adhesive application machine 21 Nozzle 22 UV curable adhesive 23 UV irradiation equipment

Claims (2)

A rotary encoder rotating body composed of a hub member fixed to a rotation shaft to be measured, a disk member fixed to the hub member and having a predetermined pattern, and a magnet bonded to the hub member;
A circuit board for calculating the rotation amount of the measurement object based on the detected signal from the predetermined pattern;
It consists of a mold member that rotatably houses the rotary encoder rotating body,
The rotary encoder according to claim 1, wherein the hub member has a through hole, and the photocurable adhesive filled in the through hole is cured to bond the hub member and the magnet.   The rotary encoder according to claim 1, wherein the photocurable adhesive is an ultraviolet curable adhesive.

Images